Re: LF: Re: 74LS196N 74S196N Difference ?? L or LS

["Graham" <g8fzk@g8fzk.fsnet.co.uk>]

Alan,

 

Yes , had a better  look on the  web  last  night, actually  found the  data  sheet amongst the  advert links   ,  its the  last  in the   5 MHz to  500 Hz  fixed reference   divider    chain , no  fan out  or  in , so  as long as the  spares  'work  , should  solve the  problem ..or at least  moves the  process  on one stage ...

 

 

Tnx-73-G..

 

 

 

From: Alan Melia

Sent: Friday, May 03, 2013 1:24 AM

To: rsgb_lf_group@blacksheep.org

Subject: Re: LF: Re: 74LS196N 74S196N Difference ?? L or LS

Hi Graham yes ,in that situation I would say that's probably ok. It sounds like the A stage FF has died. There is probably more drive available from the "S" version. It will load the driving stage a bit more heavilly but you probably do not have a high fan-out. i.e.the stage driving the 196 is only driving the 196? or maybe one other gate input?

 

Alan 

----- Original Message -----

From: Graham

To: rsgb_lf_group@blacksheep.org

Sent: Friday, May 03, 2013 12:43 AM

Subject: Re: LF: Re: 74LS196N 74S196N Difference ?? L or LS

Tnx Allan

 

Yes that  makes sense  ,  the  chip that's  decided  to   double the  frequency to the  phase comparator   from   500  Hz    sq  wave to   1 Khz   1:5  pulse train  ...... thereby    ending  the   gb4fpr   472.5  session  .......   is  a  74LS196N 

 

I have  have  a few   74S196N   in the   spares box , should  be ok  as  replacement ?

 

73 -G.

From: Alan Melia

Sent: Thursday, May 02, 2013 11:13 PM

To: rsgb_lf_group@blacksheep.org

Subject: LF: Re: 74LS196N 74S196N Difference ?? L or LS

The S is fast schottky logic and will pull more current per chip than LS or TTL and will probably be slightly faster (I think without getting the spec sheets out)  LS draws less current than standard TTL but is as fast or in some cases slightly faster. The functionality is of cource exactly the same. LS will probably replace any standard TTL logic though it depends on the quality of the design to be sure that you dont get timing or race problems.

 

Alan

G3NYK 

----- Original Message -----

From: Graham

To: rsgb_lf_group@blacksheep.org

Sent: Thursday, May 02, 2013 10:45 PM

Subject: LF: 74LS196N 74S196N Difference ?? L or LS

74LS196N    74S196N  Difference  ?? L or  LS     divider   chip

 

What is the  difference  anyone  ??

 

 

 

Tnx -G.